factory?

If you have a Double Auto of any variant with multiple barrels are the barrels marked such that you know it's a factory set? Ditto a case?
Bill

To the best of my knowledge be a no in the markings department.
However barrels were individual hand fitted to match the particular gun so look for any recent out of place file marks or a different feel or movement between them when fitted. That's always a clue or giveaway
The factory fit is very neat and precision when adjusted properly including the reamed hole /pin forend fit on aluminium adjuster nut.

I have a Double Auto. I couldn’t shoot it well so I bought another barrel for it with a Poly Choke — that extra weight really smooths my swing. Unfortunately it didn’t fit. I brought it to Art and after two strokes with a file it fit perfectly.

Another tip is how smooth the forend latches and feels resistance wise and locks into the fixed position between barrels. That's how you can tell if same person did the final fit on both.
When you fit a different barrel from another gun in trained hands , with a bit of sensory perception they can feel looser or tighter and the quality of the fit completely depends on the skill of person using the file and their patience to get it right. You can take metal off but can't put back on easily.

The shop that has it is about an hour from me. I may go see it tomorrow.'
Bill

Sorry it has taken me a while.
It is a black 1966 (6A50xxx)
Metal looks good but the stock has many small usage marks.

Does the Browning historian still exist?
I have paid for a letter for a Superposed but will he verbally answer a question?
I didn't see a Historian link on the Browning web pages.

Thanks,
Bill

I found the Historian , he's 9 months out on letters and he can't quickly answer a detailed order question.